A deep-pocketed restaurateur shelled out nearly three-quarters of a million dollars for a single tuna fish at Japan's Tsukiji fish market on Thursday, smashing a previous record.

The 269kg bluefin -- caught off the coast of Japan's northern Aomori prefecture -- stood at an eye-popping 56.49 million yen ($710,000) when the hammer came down in the first auction of the year.

The figure dwarfs the previous high of 32.49 million yen paid at last year's inaugural auction at Tsukiji, a huge working market that also features on many Tokyo tourist itineraries.

Thursday's winning bidder was Kiyoshi Kimura, president of the company that runs the popular Sushi-Zanmai chain.

At around 210,000 yen per kilogram, a single slice of sushi could cost as much as 5000 yen ($63), but the firm plans to sell it at a more regular price of up to 418 yen ($5.20), local media reported.

"I wanted to win the best tuna so that Japanese customers, not overseas, can enjoy it," Kimura said, referring to a Hong Kong sushi restaurant owner who bought the previous year's record tuna.

Decades of overfishing have seen global tuna stocks crash, leading some Western nations to call for a ban on endangered Atlantic bluefin tuna.

Japan consumes three-quarters of the global catch of bluefin, a highly prized sushi ingredient known in Japan as "kuro maguro" (black tuna) and dubbed by sushi connoisseurs the "black diamond" because of its scarcity.